Comparing with existing thin film transistor liquid crystal display devices, active matrix organic light emitting diode (AMOLED) display devices provide more brilliant colors and have wider color gamut.
In order to drive an AMOLED panel, three electric signals (one electric signal for supplying power for an electroluminescent (EL) film, one electric signal for supplying power for calculation or logical operation devices, and one electric signal for supplying power for a system) are required. As shown in FIG. 1, the three electric signals are VCC signal, ELVDD signal and ELVSS signal, respectively.
In the related art, the above three signals are generated by different power structures, respectively. Respective direct current-direct current (DC-DC) conversion units are required for generating the above signals. Efficiency of the existing DC-DC conversion unit is usually about 85%, and loss in conversion process are dissipated by the form of heat. This electrical energy consumption is also included in a total power consumption of the whole electric device. Thus, the more the DC-DC conversion units in the whole power supply structure are, the higher the power consumption of the whole device is.
Although the AMOLED panel is taken as an example for illustrating the problem of high power consumption/low power efficiency in the related art. It should be understand that other power structures which separately generate positive voltages and negative voltages have the above problem, which will not be listed here one by one.